Thread cutter for looms



April 9, 1946. R. G. TURNER 2,398,264

THREAD CUTTER FOR LOOMS Filed Aug. 26, 1944 2 Sheets-Sheet 1 IIL-1 GAM T HW April 9, 1946. R. G. TURNER 2,398,264

THREAD CUTTER FOR LOOMS Filed Aug. 26, 1944 Sheets-Sheet 2 Ihn-.il

fwwenior@ Patented Apr. 9, 1 946 THREAD CUTTER FOR LOOMS Richard G. Turner, Worcester, Mass., assignor to Crompton & Knowles Loom Works, Worcester, Mass., a corporation of Massachusetts Application August 26, 1944, Serial No. 551,288

Claims. This invention relates to improvements in weft thread cutters for looms and it is the general object of the invention to provide a, thread cutter so constructed that the blades thereof wil1 operate satisfactorily Awhile moving laterally of an actuator mounted on some part of the loom, such as the lay.

In certain types ofweft replenishing looms it is customary to use a. cutter to cut the thread in the shuttle box at va point close to the delivery eye of Vthe shuttle on transferring beats of th'e loom, so that the outgoing bobbin can unthread the shuttle eye and remove part of the thread from the shuttle box. Cutters of this type are actuated by some part mounted on the lay during forward movement of the latter, and the cutting should be completed before the lay reaches front center position to avoid breakage of the thread when the outgoing bobbin moves downwardly from the shuttle as the lay approaches its front center position. A thread cutter of this general type. as set forth in my prior Patent No. 2,226,290, comprises a fixed and a movable blade 4mounted on a lever swinging about a pivot forif the movable Jaw of the cutter has worn a groove in the actuator.

In order that the cutter may have the proper shearing operation the movable blade should be Imounted so that it is capable of slight relative movement with respect to the fixed cutter blade. If for any reason the actuator tends to h'old the movable blade against lateral movement with the cutter mechanism as the latter moves laterally with respect to the shuttle box and lay, the movable blade will be tipped to an improper position for correct cutting relatively to the ilxed blade. It is an important object of my present invention to provide means by which an actuating force may be communicated from the lay to the movable jaw through such means as will avoid the tipping of the movable blade. The transmitting means may be in the form of a roll mounted either on the movable cutter blade or the lay and so mounted that it can turn while communicating an operating force to the cutter mechanism.

It is a more particular object of my present invention to provide a cutter mechanism with a movable jaw having two stops thereon for engagement with a part of the mounting structure and employ a spring for the movable blade which will bear against the mounting at a point between the stops of the movable blade. In this way a single part of the mounting, such as a lug pro- Jecting therefrom, serves not only to limit angular movement of the movable blade in two directions. but also causes the spring, which may be made o1' flat sheet steel, to hold the `movable cutter blade in proper cutting position relatively to the stationary blade.

Itis a further particular object of my present invention to provide a thread cutting mechanism wherein the movable blade is under control of a spring which is confined within a restricted space which, although not entirely inclosed, is nevertheless protected against entry of weft ends by the aforesaid ilat spring of the movable cutter blade and .the lug on the mounting.

With these and other objects in view which will appear as the description proceeds, my invention resides in the combination and arrangement of parts hereinafter described and set forth.

In the accompanying drawings, wherein two forms of my invention are set forth:

Fig. l is a plan view of part of a weft replenishing loom showingth'e preferred form of my invention applied thereto,

Fig. 2 is an end elevation looking in the direction of arrow 2, Fig. 1,

Fig. 3 is an enlarged side elevation of the cutter mechanism in normal position looking in the direction of arrow 3, Fig. 1,

Fig. 4 is a plan view looking in the direction of arrow 4, Fig. 3,

Fig. 5 is a side elevation looking ln the direction of arrow 6, Fig. 4, and showing the side of the cutter mechanism opposite to that set forth in Fig. 3,

Fig. 6 is a rear elevation of the cutter mechanism looking in the direction of arrow 6, Fig. 3,

Fig. 7 is a view similar to Fig. 5 but with the at spring for th'e movable cutter blade removed to illustrate the space in which the return spring for the movable blade is located,

Fig. 8 is a view similar to Fig. 'I but with the movable blade removed, i

Fig. 9 is a view similar to Fig. 5 but with the movable blade moved to cutting position when the lay is on the front center position and with the dat steel spring removed,

Fig. l is an enlarged vertical section on line Id-H2,Fig. 5, A

Fig. ll is a view similar to Fig. 9 but showing a modified form. of the invention wherein the force transmitting roll is mounted on the lay, and

Fig. 12 is a detailed plan view looking in the direction of arrow i2. Fig. 11.

Referring particularly to Figs. 1 and 2, I have shown a loom lay I8 having a shuttle box ii to receive a shuttle S carrying a weft bobbin B which is located between front and back walls I2 and i3.

respectively, of the shuttle box when the shuttle is in transfer position on the replenishing side of the loom. Picker mechanism designated generally at P is provided for moving the shuttle out of the box in usual manner and the shuttle is provided with a thread delivery eye E of any ap' proved construction. The front wall I4 of the shuttle is provided with a slot i5 which registers with a second slot I6 in the front wall I2 of the box when the shuttle is properly boxed. The slots it and i6 are between the delivery eye E and the adjacent selvage not shown which is to the left of the structure shown in Fig. 1. The weft thread W leads from bobbin B through the shuttle eye and then to the left along the front shuttle wall i4 and across the slot i5, leaving the left end of the box as indicated in Fig. l and extending to the selvage.

Fig. l also indicates a transferrer arm 2Q mounted on a stud 2| carried by a fixed part 22 of the loom. The transferrer arm is acted upon by the usual heavy coil spring 23 which normally holds the arm raised in nontransfer ring position. The transferrer arm has a lateral extension 24 and the stud 2| projects as at 25 to the` right from the spring 23. A support 26 secured as at 21 to the stud extension 25 carries a vertical stud 28 on which is pivoted a lever 29. A torsion spring 36 surrounds the stud 28 and has its ends attached respectively to the stand 26 and the lever 28 and acts to turn the lever in a counter-clockwise direction as viewed in Fig. 1. The right end of lever 28 may be provided with a hub 3| and a securing screw 32 to hold the shank 33 of the cutter mechanism designated generally at C.

In the matter thus far described the extensie 24 engages the left arm 34 of the lever 29 and holds the hub 3| in forward position against the action of spring 30. the spring 23 being amply strong to overpqwer the spring 30 for this purpose. The cutter mechanism C is therefore held normally inactive, and does not enter the slots IE and I6 as the lay beats forwardly. On a transferring beat of the loom, however, descent of the transferrer arm will move the extension 24 forwardly, whereupon spring 30 acts on lover 28 to move the hub 3| and cutter mechanism C rearwardly so that the latter can enter the slots I5 and I8 for the purpose of cutting the weft thread W at a point adjacent to but to the left of the eye E. Except as noted hereinafter the mechanism thus far described may be similar in its construction and mode of operation as that set forth in my previously mentioned patent.

Referring more particularly to Figs. 3 to 10. I have shown the shank 33 as being in the form of a cylindrical rod to the rear end of which is secured a head 40 of rectangular cross-section and having a laterally extending lug 4|. A stationary cutter blade 42 is fastened to the head 43 by a aseaaea tending cutter finger 44 provided with an upwardly` facing cutter edge 45,; see Fig. 8. A second movable cutter blade is formed with a rearwardly extending cutter finger 6|, and has upper and lower forwardly extending stop arms 52 and 53 located. respectively, above and below the lug 4|. A bolt 55 extends through the movable and stationary cutter blades and is tapped into the head 4t to provide a pivot for the movable blade 56 and additional securing means for the stationary blade 42. The screw 5E cooperates with the previously described screw 43 to hold blade 52 stationary with repect to the head 40. The finger 5i has a cutting edge 56 on the under side thereof for cooperation with cutting edge 45.

A flat spring made preferably of tempered sheet steel has a forward broad end 8| which is mounted to slide along the vertical surface G2 of lug 4|. The rear end of spring 50 is tapered as at 83 and has its reduced end bent and extended into a small perforation or recess 64 formed in the rear end of finger 5|. in position by the head $5 of the screw 55 which normally creates a deflection of the spring, see Fig. 4, tending to move the cutting edge 56 over the finger 42, as shown in Fig. 4. For this purpose the screw 55 fits loosely in a hole 68 in the movable cutter jaw, see Fig. 10, thereby permitting a slight angular movement of the cutter 50 with respect to the head 40 and the stationary blade 42.

The top arm 52 of the movable cutter blade may be perforated as at B1 to receive the upper end of a small tension spring 88 the lower end of which is held by a short stud 69 projecting laterally from the head 40 adjacent to the lug 4|. The stud 68 is located between the forward broad end of the spring 60 and the head 40 and between the top and bottom arms 52 and E3 of the movable cutter blade.

Welded to or otherwise appropriately secured to the rear part of arm 53 is a. U-shaped carrier lil supporting a stud 1| on which is rotatably mounted a roll 12. The axis of the stud 1| is preferably xed with respect to the movable blade 50 in the preferred form of the invention shown for instance'in Fig. 3, and the roll 12 is free to rotate about the stud 1|. The carrier has top and bottom arms I5 and 16 which are connected by a substantially vertical section or part il of the carrier which is welded or otherwise secured to the movable blade 50.

For operating the preferred form of thread cutter mechanism I provide the lay with an actuator or operator shown more particularly in Figs. 1 and 9, and comprising a stand 80 secured to the lay I0 and having a horizontal arm 8| to which a second horizontal arm 82 is bolted as at 83. The second arm is provided with an upright front wall 84 positioned for engagement with the roll 12.

In operation, the lever 29 and cutter mechanism will normally be stationary so that the roll 12 is not engaged by actuator or operating wall 84 when the lay reaches its front center position. When the lever 29 moves at the time of transfer, however, it effects rearward movement of the hub 3| and cutter mechanism, the latter swinging around stud 28 and the fingers 42 and 5| of the two cutter blades crossing slot 4I8 and entering slot I5 in the shuttle at such a level that the weft end W will enter the notchbetween said fingers 42 and, 6l. During the latter part of this rearwardmovement of the cutter mechanism, and as the lay is advancing, the actuator wall 84 will screw 43 and is provided with a rearwardly ex- 75 engage roll 12 and rock the movable cutter 60 The spring 80 is held' aseaaea from the position shown in Fig. l to that indicated in Fig. ilv for the purpose of cutting the weft W. In the cutting operation wall I4 exerts a forwardly directed force on the cutter mechanism, swinging the latter about the stud 2t in a direction to move the cutter mechanism to the right as viewed in Fig. 1. During this last named movement the roll 'I2 rolls along the wall B4, and eventually the cutter blade 50 will have been turned a sulcient angular distance as viewed for instance in Fig.v 9 so that its lower stop arm 53 will engage the lug 4| of the head 40. This engagement does not occur until after the ngers 42 and Il have crossed each other suillciently to insure cutting of the weft ends. Thereafter the wall 84 acts through roll 12, carrier 10, arm t3 and lug 4l to move the cutter mechanism as a whole forwardly.

During angular movement of the cutter blade 50 the spring 88 is stretched and upon rearward movement of the lay spring 28 will move the cutter mechanism rearwardly until the advancing arm 84 engages the extension 24 of the transferrer arm, whereupon movement of the cutter mechanism as a whole is reversed and roll 12 moves forwardly away from the actuator wall 84 and is returned to normal position as the transferrer arm reaches its normal high position.

In the modified form of the invention shown in Figs. l1 and 12 a roll 90 similar' to roll 12 is mounted on a small stand 9| secured as at 92 to a bracket or the like 93 secured to the lay I0. The lower arm 63 of the movable cutter blade 50 has welded or otherwise secured thereto a plate 9s along which roll 90 can roll during the cutting operation. The operation of the modified form of the invention is substantially the same as that described for the preferred lform.

As previously stated, the opening 66 in blade 50 through which screw 55 passes is large enough to permit movement of blade 50 angularly in planes passing through the axis of the screw 55.

`The reason for this relationship is to permit the fiat steel spring tu to hold the cutting edge 56 of the upper nger l5i over the lower finger 42.

As finger El descends during a cutting operation it moves outwardly, or upwardly as viewed in Fig. 4, as cutting edge 56 moves along cutting edge 45. Because of the loose fit between screw 5B and blade 60 the latter could also tip slightly in a clockwise direction as viewed in Fig. 10, but such tipping would move finger 60 away from nger t2 and destroy the cutting relation of the two blades. Such tipping would occur ii' arm i 5t were prevented by actuator 8d from moving to the right. Fig. 10, as thecutter mechanism as a whole moved laterally' as described. The rolls l2 and 90, however, roll along their respective cooperating members at and 94 and prevent the aforesaid tipping, The blades therefore remain in' their correct cutting relationship throughout the cutting operation. The rolls are thus seen to have an advantage over the structure set forth in the aforesaid patent in that no effective force is brought to bear on the blade 50 tending to disturb its proper cutting relationship with respect to the fixed blade B2. The mechanism set forth herein can operate over a long period of time without the formation of any grooves or the like in the parts which transfer the actuating force from the lay to the-movable cutter blade and the latter will therefore continue to operate successfully.

As will be apparent from Figs. 4, 5 and 7, the spring 8s and the lug I0 are located within a partially inclosed space the front of which is deilned by lug 4i, one side of which is deiined by the broad front end of the spring B0. and the opposite side of which is deilned by the head 40, and the rear part of which is defined by the front end of the fixed cutter blade 42. Furthermore, the arms 52 and 53 lie over and below this space and the latter is therefore seen toibe protected against entry by weft ends which might otherwise become entangled with the coils of the spring 66 when` the latter vexpands and subsequently contracts. .e

From the foregoing it will be seen that I have provided simple means .by which the thread cutter mechanism of a weft replenishing loom can be operated by a force derived from the lay and transmitted through an actuator or operator to the movable c'utterblade of a cutter mechanism mounted for lateral motion with respect tothe lay during its period of operation without disturbing the proper cutting relation of the two blades. It will also be seen that the roll may be located either on the cutter mechanism or on the lay, and that because of the roll no effective force is exerted on the cutter 50 suillcient to tip it away from finger 42 and the -normal plane of its angular movement during a cutting operation. Also, the small spring 6B operates in a space which is deined by the several parts of the cutter mechanism and is thereforeprevented from becoming entangled with the threads which are parted by the cutter mechanism; Furthermore, th e cutter 50 is provided with the two arms 52 and 53 which limit its angular movement about the screw 55 and the lower arm 53 also serves to transmit a force from the lay to the shank 33 and lever 29 to move the latter forwardly to absorb any excess movement of the cutter mechanism induced by the lay after the cutting operation has -been completed. The lug 4l not only serves as stopping means for arms 52 and 53, but also cooperates with the head of screw B5 to deflect spring 60 as indicated in Fig. 4.

Having thus described my invention it will be seen that changes and modifications may be made therein by those skilled in the art without departing from the spirit and scope oi' the invention and I do not wish to be limited to the details herein disclosed, but what I claim is:

1. In weft thread cutting mechanism for a loomA having a support. a head carried by the support,

a lug extending laterally from one side of the` head, a cutter blade fixed to said one side of said head, a second cutter blade pivoted with respect to the head, upper and lower stop arms on said second blade, one above and the other below said lug, a fiat spring supported by the head and having one end thereof in engagement with said second blade and having the other.

end thereof engaging said lug and spaced-from said head, and a spring having one end fixed with respect to the head and having the other end thereof attached to said second blade to hold one of said `stop arms normally against said lug, said second named spring located behead, a-second cutter blade pivotally mounted with respect to the head, said fixed blade lying between the head Yand said second blade, a 'dat spring on that side of the second blade opposite- -to the first named blade and having one end lloom having a movable support, a head :fixed with respect to the support, a cutter blade xed to the head, a second cutter blade pivotally mounted with respectto the head, a lug formed on the head, an upper stop arm on the second blade extending over the lug, a lower stop arm on the second blade extending below the lug, and spring means operatively interposed between the head and the second blade normally holding the ilrst named stop arm down in engagement with the upper part of the lug, the second stop arm when raised against the action of said spring into engagement with the lug due to pivotal movement of the second blade with respect to the head and when being moved thereafter toward the lug being operative to transmit a force from the second blade through said second arm and lug to the support to move the latter.

4. A cutter blade for a weft cutting mechanism of a loom having a supporting head provided with a stop, said blade being formed of a at sheet of metal and having provision for pivotal mounting on the head and having a cutting edge and having also spaced upper and lower stop arms for engagement with said stop, and a rolly mounted on the lower stop, arm for rotation about an axis substantially parallel to the plane of the blade.

5. A cutter blade for a loom weft cutting mechanism having a support provided with a, stop. said blade having a rearwardly extending cutting nger, two spaced forwardly extending stop arms for alternate engagement with the stop, and the blade having provision between the cutter finger and the stop arms for pivotal mounting on the support.

6. A cutter blade for a loom weft cutting mechanism having a support provided with a stop, said blade formed of a sheet of flat metal and having a rearwardly extending cutting finger, two spaced forwardly extending stop arms for alternate engagement with the stop, the blade having provision between the cutter finger `and the stop arms escasas for pivotal mounting yon .the support. and one of said stcparms beingprovided with a roll rotatable thereon aboutan axis ,parallel to the plane of the blade.l

'7. A weft thread cutting unit `comprising e. head provided with a stop. a cutter blade fixed to said head, a second cutter blade ypivoted to said head and having upper and lower arms lying on opposite sides of said stop for alternate engagement therewith, andk a flat spring supported by said head and moving with the'secondcutterblade and sliding along said stop when said second cutter blade moves pivotally relatively to said head, said spring urging said second blade toward the first Ablade during relative angular movement of the cutter'blades.

8. A weit thread cutting unit comprising a head provided with a. lateral stop, a cutter blade fixed to said head, a. second .cutter blade pivotedon said head and having a stop arm extending over said stop and having another stop arm extending under said stop, said arms arranged for alternate enga-gement with said stop, and a ilat spring supported by said head and moving angularly with the second cutter blade and having a portion thereof in sliding engagement with said stop.

9. A weft thread cutting unit comprising a head provided with a stop, a cutter blade xed to said head, a pivot screw supported by said head, a second cutter blade pivotally mounted on said screw 'and having a cutting nger to cooperate with the first named blade and having a top arm extending over said stop and a bottom arm extending under said stop, said arms arranged to engage said stop one at a time, and a flat spring pivotally mounted on said screw and held by the latter against the second cutter blade and turning angularly with the latter, said at spring having a portion slidably engaging said stop. f

l0. A weft thread cutting unit for the lever of a weft cutting mechanism, said unit comprising a head provided with a stop and a shank for attachment to the lever, acutter blade fixed with respect to the head, a second cutter having a cutting nger to cooperate with the first named cutter blade and having an upper arm extending over said stop and a bottom arm extending under said stop, said arms being arranged for alternate engagement with the stop, pivot means on the head between said ilnger and said arms around which the second cutter blade moves angularly with respect to said head, and a flat spring held in position jointly by said linger and said pivot means and moving with the second cutter blade and slidable along said stop.

-RICHARD TURNER. 

